The real question, of course, is when Wet, Rogue Warrior and Wayne Gretzky Hockey are going to be added.
The Elder Scrolls Online and Fallout: New Vegas are also being added to the service, but only for console or cloud players.
Xbox Game Pass is best when it's offering up good games that you maybe didn't get around to buying, though, so maybe this is your chance to finally play Prey or The Evil Within. Skyrim and Dishonored are included among the 18, but there's a decent change you already own those. Microsoft made the announcement in a blog post, and there are 18 of them coming to Xbox Game Pass For PC. Bethesda's games are beginning to arrive on Xbox Game Pass tomorrow.